There are a variety of applications where oil and water resistant, flexible, gas permeable footwear is useful. For example, in the clean up of chemical waste sites, a prevalent problem in our country today, there is a need for protective footwear which (1) will resist the passage of both oil and water-based compositions and (2) is gas permeable, thus allowing passage of air and water vapor and thereby permitting transmission of air and moisture (perspiration) through the footwear from the body side to the atmosphere. In this type of application, detergent and solvent resistant characteristics are also valuable since the nature of the compositions encountered is not always known. Similarly, the need for protective footwear for military personnel who, in the field, may be exposed to deleterious oil and water-based aerosols by virtue of field conditions, provides additional incentive for the development of light-weight, flexible or pliant, microporous (thereby being gas permeable), oil and water resistant structures that can be used in the manufacture of protective fabric and which can be tailored to form socks, shoes, boots and the like.
The subject invention is directed to composite structures which provide the desired properties in such applications.